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    Heating calc (5 Posts)

  • BenWoj BenWoj @ 1:23 PM
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    Heating calc

    Hey everyone,new to the forum and new to radiant heat. I purchased a house that currently has hydronic baseboard heating as well as infloor heating. I have the opertunity to remove the baseboard heating and install infloor heating so I've been trying to read up as much as possible. I'm having a hard time though with gpm, pex size and water temp. I did a heat loss calc for the room,(1518), but other then that I'm kinda stuck. I'm not sure how to apply this calculation for whatever else I may need.

    Thanks for the help.
  • Rich Rich @ 4:09 PM
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    that be all you want to heat ?  This is a very small area that you are heating or is it completely interior .  Either way I am curious as to the size of this room . 
     To answer your questions .   GPM =   . 3036  @ 10* Delta T .  3/8" barrier pex will be more than adequate , 1 loop .    Need finish floor material and indoor design temp you wish to give temp . Are you sure that 1518 is the load ?
    You didn't get what you didn't pay for and it will never be what you thought it would
  • BenW0j BenW0j @ 8:13 PM
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    Heat calc

    You have me second guessing myself now. Let me do my calc again and I'll get back.

    On a side note. If I had a room with 1/2 pex with two loop at 300. Would I gain anything if I was to make three loops at 200? And if there is a gain, is it worth it or something minimal?

    Thx, be back with those heat loss figures.
  • Rich Rich @ 9:41 PM
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    water temps may be a bit south of 90 .  Have a bit bigger room in a project I am bidding right now . Room is 2200 heat load with 3* outdoor temp , 70* indoor and requires 91* , 2 loops with 8" spacing and 115' each in the panel . This does not include leader lengths . Leaders are the pipe from your manifold to where the tube enters the floor to be heated .  Now Ben , if you are planning on running this radiant as part of a baseboard zone I urge you not to . It should be it's own zone .  Are you planning on doing more than one room ? Kinda silly not to do more while you're at it .
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on August 22, 2013 9:46 PM.
  • BenWoj BenWoj @ 7:36 AM
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    The room I'm looking to install is a large room (27 x 15). Which I know I did my heat loss calc wrong looking at it again. There are two zones upstairs, the room is currently one zone by itself so I was thinking of removing the baseboard completely and just running infloor heat. Doing a quick estimate, it looks like I'd get two loops at about 285 plus lead length and was thinking it would help with heating the room if I made it 3 loops instead which would be around 200ft each plus lead.

    The rest of the upstairs is baseboard heat as well and on another zone. Since ive gutted the whole upstairs to the studs, I was going to use that zone for the second bedroom and remainder of space (20 x 15, 10 x 12). Not sure how many loops yet, haven't gotten that far.
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